Idaho · THREADEX · 1875–2026
Boise, ID
43.567°N, 116.241°W · station BOIthr · 152 years of record
99°F
HOTTEST JUL 18 SINCE 2024
forecast high · Jul 18
NWS NDFD forecast high temperature for Boise.
This Day in History · Jul 18
Today ranks
#15 / 150
warmest Jul 18 in 150 yrs of record
Hottest Jul 18 ever
106°F
set in 2009
Coolest Jul 18 ever
67°F
set in 1916
Hottest Jul 18 — Year by Year
Every year's high on Jul 18 at Boise. The forecast line shows where today lands; the ringed bar is the hottest on record.
| Forecast high · Jul 18 | 99°F |
| Hottest this date since | 2024 |
| This-date record | 106°F |
| This-date rank | #15 of 150 |
| Hottest at any time since | 2026 |
| All-time record | 111°F (1898) |
| Odds to tie/break | 2.0% (daily) |
| Period of record | 1875–2026 |
The hottest and coldest ever recorded at Boise in each calendar month, and for the whole 1875–2026 record — with the year each was set.
| Month | Record High | Record Low |
|---|
| Jan | 66°F2024 | -28°F1888 |
| Feb | 71°F1992 | -15°F1989 |
| Mar | 83°F2026 | 5°F1906 |
| Apr | 92°F1898 | 11°F1936 |
| May | 100°F1897 | 22°F1982 |
| Jun | 110°F2015 | 30°F1901 |
| Jul | 111°F1898 | 35°F1986 |
| Aug | 110°F1961 | 32°F1892 |
| Sep | 104°F2022 | 23°F1926 |
| Oct | 94°F1992 | 11°F1971 |
| Nov | 78°F1999 | -10°F1896 |
| Dec | 70°F1939 | -25°F1990 |
| All-time | 111°F1898 | -28°F1888 |
Records set or tied at Boise so far this year — through Jul 11.
Record Highs in 2026
4 broke
plus 2 tied — daily record highs set this year
Monthly high record this year: Mar (83°F)
Record Lows in 2026
0 broke
plus 0 tied — daily record lows set this year
Current run
9 days
consecutive days with a high ≥ 90°F
Longest ever
50 days
record run, ended Aug 22 1875
So far in 2026
17 days
days with a high ≥ 90°F this year
Normal high & low by month, from Boise's own 1991–2020 record. Today's normal high: 93°F · forecast is +6° vs normal.
Sun & Daylight Today
| Sunrise | 4:16 AM |
| Sunset | 7:25 PM |
| Solar noon | 11:50 AM |
| Daylight | 15h 10m · losing 8 min/wk |
Local standard time (no DST), level horizon.
Location
Boise's observed daily high for the last six weeks — a white ring marks any day that broke or tied its daily record for that date.
Every day this year against Boise's own record — the record high, the normal, and the full span ever seen. A shareable look at where the year stands.
Each cell is one day's high at Boise, coloured by temperature — 152 years of record, so heat waves read as warm streaks and cold snaps as blue.
How many days a year hit a given high at Boise — counted through Jul 18 each year, so you can see whether 2026 is running hot. Pick a threshold:
17 days ≥90°F so far in 2026 — tied for the 41st most in 152 years. Normal for this point: 13. Record: 34 in 2021.
A ready-to-share summary of Boise's outlook — post it, or link this page.
See Boise on coldestsince.com →